Following the introduction of reserpine and chlorpromazine into psychotherapeutic medicine in the early 1950's, great effort has been expended in the search for other tranquilizing agents having improved biological profiles.
It has now been found that certain indoles, and more particularly, a series of 2-phenylthio- and 2-phenylsulfinylpropyl-5-aryl-1,2,3,4-tetrahydro-.gamma.-carboline derivatives, are effective as tranquilizing agents.
.gamma.-Carbolines are not new in the chemical and patent literature; antihistamine activity is reported in British patent 721,171 and U.S. Pat. Nos. 2,786,059 and 3,409,628; antidepressant activity in U.S. Pat. Nos. 3,419,568, 3,687,960, 3,705,902 and 3,718,657; antitrypanosomal activity in U.S. Pat. No. 3,654,289 and German Pat. Nos. 2,117,286 and 2,115,738; depressant and analgesic activity in U.S. Pat. Nos. 3,466,293, 3,502,688 and 3,382,250; and tranquilizing activity in U.S. Pat. Nos. 3,687,961 and 3,755,584.
Belgium Pat. Nos. 827,451 claims a series of .gamma.-carbolines and pyrrolo[3,4-b]indoles as tranquilizing agents.
None of these aforementioned references suggest the compounds of the present invention or the use thereof as tranquilizing agents.